Editing Office web apps on an iPad

Hi, I am wanting our students to be able to edit their Word and PowerPoint documents, via Office Web Apps on their iPad. We are about to implement a Sharepoint environment where students will have their own My Site. This is where they will store Word and PowerPoint documents they are working on.

I want them to be able to edit these documents in a browser. iOS5 supports this but it's clunky with Safari and a little better with iCabMobile. However neither browser supports clipboard so the students can't copy an image and paste into the document.